1. Field of the Invention
The present invention relates to closure devices and more particularly to hand operable sealing closures.
2. Description of the Related Art
It is a common practice to use wraps for enclosing the open ends of the containers. The wraps such as Saran wrap are normally derived from polyvinylidene chloride polymers that have adhering properties so that they cling to a container lip. In the course of time, these wraps loose their adhering strength and easily get punctured and/or torn. These wraps are of light-weight and normally weakly adhere to the container lip, which require the user to put substantial efforts in hermetically sealing the containers. The operation of these wraps is not without other problems. For example, the inability of these wraps to evacuate air from the containers readily spoils the stored contents in a short period of time.
The closures that have the ability to form the vacuum seal normally require an external vacuum source, such as vacuum pump for creating the vacuum. These closures lack their ability to evacuate the containers in the circumstances such as for example, outdoor picnic, traveling, embarking on a trip, where the source of vacuum is unavailable.
The operation of these closures is frequently a two handed practice in which preferably both hands are required to stretch the wrap against the rim of the container to form the hermetic seal. The lack of the ability of these closures to be operated using a single hand limits their convenience for the users that are physically handicapped with one hand.
A sealing lid is needed that exerts sufficient pressure to substantially enclose and evacuate the container and operates using a single hand to form a hermetic vacuum seal with the container.